Scooters are well known vehicles used as a means of personal transportation in a variety of situations. One conventional leisure scooter which is sized to accommodate adults and children is disclosed in German Utility Model 91 12 537 (hereinafter the German UM '537) as having oversized wheels for purposes of providing good rolling features so that it may be environmentally friendly for purposes of exercise and/or leisure, as well as providing a means of locomotion, e.g., for shopping, intra-company transportation, and the like.
One problem associated with the conventional leisure scooter disclosed in the German UM '537 is its relatively high weight and awkwardness due to its larger frame with two relatively large wheels. As a result, the leisure scooter is difficult to accommodate in the trunk of a passenger car, typically requiring the trunk of the car to remain at least partially open when being transported therein. Furthermore, because of its size and weight, the leisure scooter cannot be brought aboard public transportation vehicles, such as buses, trains, subway cars, and the like. As a result, the leisure scooter disclosed in the German UM '537 cannot be easily transported over long distances by the user and thus is not available for the user's local transportation needs.
It would therefore be especially desirable if a scooter were provided is as compact and lightweight as possible and thus could be used as personal transportation in metropolitan areas since it could then be taken onto public transportation vehicles. It would furthermore be desirable if such a scooter exhibited good rolling capabilities so that it could be safely and efficiently operated by both children and adults thereby making its manufacture more simple and economical. It is towards providing such an improved scooter that the present invention is directed.
Broadly, the present invention is embodied in a scooter having front and rear wheels of significantly different size. More particularly, according to the scooter of this invention, a relatively large-radius wheel is employed as the steerable front wheel, while a relatively small-radius wheel is employed as the unsteerable rear wheel. Advantageously, the radius of the front wheel is at least four and more preferably at least about eight, times greater than the radius of the rear wheel.
Several advantages ensue from the relatively larger front wheel and smaller rear wheel in the scooter according to this invention. For example, the overall length and weight of the scooter can be decreased significantly as compared to prior art scooters. Thus, a compact personal transportation vehicle is provided that can be used for many different purposes since it can be operated easily and safely and can itself be transported without problems in private and public transportation vehicles and in building elevators.
Because of the larger size of the front wheel, its axle is spaced physically above the substantially horizontal plane of the footboard on which the user stands during the scooter's operation. The axle of the smaller rear wheel, on the other hand, is disposed near the footboard plane, and most preferably is disposed physically below the footboard plane. It is possible, however, that the axle of the smaller rear wheel can be disposed in the plane of as well as above the footboard plane, if desired. As a result, both adult and child users can step on and off the footboard both laterally and from the rear with ease since the footboard is located fairly close to ground surface and since the rear wheel does not impede such movements.
It has surprisingly been discovered that the scooter according to this invention rolls extraordinarily easily and can be steered virtually effortlessly. It is presumed that the relatively large-radius front wheel and relatively small-radius rear wheel, with their respective varying axle planes, are responsible for such functions. In addition to the functional benefits mentioned above, the relatively large-radius front wheel rolls easily over ground irregularities without getting stuck. The small-radius rear wheel is responsible for decreasing the length of the scooter so that it can be made as compact as practical. That is, the footboard does not need to be any larger than what is needed for the user's feet to be placed side-by-side to one another during operation. The low plane of the footboard also creates a relatively low center of gravity for the scooter with the user standing on it thereby promoting increased stability. The increased stability, in turn, permits the scooter of this invention to be operated by people with unsteady balance (e.g., elderly persons, children and the like).
The frame of the scooter according to this invention includes the planar footboard as a rear component and a front component which is connected to a forward end of the footboard and is curved upwardly therefrom so as to subtend a circumferential segment of the large-radius front wheel. A steerable yoke assembly is journalled to the forward end of the curved frame component to allow the large-radius front wheel to be steered by the operator (e.g., via a conventional handle bar assembly).
The small-radius rear wheel can be formed of one or more rollers. When a pair of such rollers are employed laterally to one another, the stability of the scooter can be further increased (e.g., due to its "three-point" contact with the ground surface). The rolling efficiency of such a multi-rear wheel scooter can also be increased to an extent that relatively broad, low riser steps can be traversed (e.g., escalator steps).
The scooter of this invention can be equipped with a parking stand located under the footboard that is pivotal into an operative position by the operator when desired to allow the scooter to stand upright during inactive periods. The rear end of the footboard may also be provided with a depending skid brake by which the operator may cause to come into contact with the ground surface by tilting the scooter rearwardly. Contact between the ground surface and the skid brake thus serves to slow the forward speed of the scooter to assist in its stopping and/or steering.
The scooter of this invention can also be provided with a variety of equipment and accessories typically used for conventional bicycles, for example, caliper brakes, running lights, fender, bell, parcel basket, and the like.
Further aspects and advantages of this invention will become more clear after careful consideration is given to the following detailed description of the preferred exemplary embodiment thereof.